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World journal of Gastroenterology 2006年第46期12卷 7547-7548页

作者： Wichian Apiratpracha jin Kee Ho james j Powell Eric M Yoshida British Columbia Transplant Society The University of British Columbia Vancouver BC Canada Division of Gastroenterology Department of Medicine The University of British Columbia Vancouver BC Canada Department of Surgery The University of British Columbia Vancouver BC Canada

A 67-year-old woman underwent an orthotopic liver transplantation for end stage liver disease secondary to chronic autoimmune hepatitis. She developed sudden massive hematochezia on post-operative day 23 with hemodynamic compromise. The source of hemorrhage was found at colonoscopy after careful irrigation and inspection to be a dieulafoy lesion situated just proximal to the anorectal junction. Hemostasis was achieved with epinephrine injection and thermal coagulation.

关键词： Bleeding Anorectal Dieulafoy Rectum

3eciphering the protein-DNA code of bacteria Ninged helix-turn-helix transcription factors

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Frontiers of Electrical and Electronic Engineering in China 2018年第1期6卷 68-84页

作者： Adam P. joyce james j. Havranek Program in Developmental Regenerative and Stem Cell Biology Washington University in St. Louis St. Louis MO 63110 USA Department of Biochemistry and Molecular Biophysics Washington University in St. Louis St. Louis MO 63110 USA

Background： Sequence-specific binding by transcription factors （TFs） plays a significant role in the selection and regulation of target genes. At the protein：DNA interface, amino acid side-chains construct a diverse physicochemical network of specific and non-specific interactions, and seemingly subtle changes in amino acid identity at certain positions may dramatically impact TF：DNA binding. Variation of these specificity-determining residues （SDRs） is a major mechanism of functional divergence between TFs with strong structural or sequence homology. Methods： In this study, we employed a combination of high-throughput specificity profiling by SELEX and Spec-seq, structural modeling, and evolutionary analysis to probe the binding preferences of winged helix-turn-helix TFs belonging to the OmpR sub-family in Escherichia coil Results： We found that E. coli OmpR paralogs recognize tandem, variably spaced repeats composed of＂GT-A＂ or ＂GCT＂-containing half-sites. Some divergent sequence preferences observed within the ＂GT-A＂ mode correlate with amino acid similarity; conversely, ＂GCT＂-based motifs were observed for a subset of paralogs with low sequence homology. Direct specificity profiling of a subset of OmpR homologues （CpxR, RstA, and OmpR） as well as predicted ＂SDR-swap＂ variants revealed that individual SDRs may impact sequence preferences locally through direct contact with DNA bases or distally via the DNA backbone. Conclusions： Overall, our work provides evidence for a common structural code for sequence-specific wHTH：DNA interactions, and demonstrates that surprisingly modest residue changes can enable recognition of highly divergent sequence motifs. Further examination of SDR predictions will likely reveal additional mechanisms controlling the evolutionary divergence of this important class of transcriptional regulators.

关键词： transcription factor SELEX winged helix-turn-helix specificity detenlainants two-component signaling

Mice with a heterozygous Lrp6 deletion have impaired fracture healing

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Bone Research 2016年第2期4卷 101-109页

作者： Travis A Burgers juan F Vivanco juraj zahatnansky Andrew j Vander Moren james j Mason Bart O Williams Center for Cancer and Cell Biology Program for Skeletal Disease and Tumor Microenvironment Van Andel Research Institute Grand Rapids MhUSA Faculfad de Ingenieria y Ciencias Adolfo Ib6fiez University Vifia del Mar Chile padnos College of Engineering and Computing Grand Valley State University Grand Rapids MI USA

Bone fracture non-unions, the failure of a fracture to heal, occur in 10%-20% of fractures and are a costly and debilitating clinical problem. The Wnt/fl-catenin pathway is critical in bone development and fracture healing. Polymorphisms of linking low-density lipoprotein receptor-related protein 6 （LRP6）, a Wnt-binding receptor, have been associated with decreased bone mineral density and fragility fractures, although this remains controversial. Mice with a homozygous deletion of Lrp6 have severe skeletal abnormalities and are not viable, whereas mice with a heterozygous deletion have a combinatory effect with Lrp5 to decrease bone mineral density. As fracture healing closely models embryonic skeletal development, we investigated the process of fracture healing in mice heterozygous for Lrp6 （Lrp6~/-） and hypothesized that the heterozygous deletion of Lrp6 would impair fracture healing. Mid-diaphyseal femur fractures were induced in Lrp6~^- mice and wild-type controls （Lrp6~/~）. Fractures were analyzed using micro-computed tomography （~CT） scans, biomechanical testing, and histological analysis. Lrp6~/- mice had significantly decreased stiffness and strength at 28 days post fracture （PF） and significantly decreased BV/TV, total density, immature bone density, and mature area within the callus on day-14 and -21 PF; they had significantly increased empty callus area at days 14 and 21 PF. Our results demonstrate that the heterozygous deletion of Lrp6 impairs fracture healing, which suggests that Lrp6 has a role in fracture healing.

关键词： bone Mice with a heterozygous Lrp6 deletion have impaired fracture healing

Experimental study on the degree and damage-control mechanisms of fuzzy-ball-induced damage in single and multi-layer commingled tight reservoirs

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Petroleum Science 2023年第6期20卷 3598-3609页

作者： Chinedu j.Okere james j.Sheng Li-Kun Fan Xiao-Wei Huang Li-Hui Zheng Pan-Feng Wei Bob L.Herd Department of Petroleum Engineering Texas Tech UniversityTXUSA College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China China Changqing Oilfield Company CNPCXi'an710018ShaanxiChina Beijing LihuiLab Energy Technology Co. Ltd.Beijing102200China

Fuzzy-ball working fluids(FBWFs)have been successfully applied in different development phases of tight *** reports revealed that FBWFs satisfactorily met all the operational and reservoir damage control requirements during their ***,the damage-control mechanisms and degree of formation damage caused by fuzzy-ball fluids have not been investigated in lab-scale studies so *** this study,the degree of fuzzy-ball-induced damage in single-and double-layer reservoirs was evaluated through core flooding experiments that were based on permeability and flow rate ***,its damage mechanisms were observed via scanning electron microscope and energy-dispersive spectroscopy *** results show that:(1)For single-layer reservoirs,the FBWF induced weak damage on coals and medium-to-weak damage on sandstones,and the difference of the damage in permeability or flow rate index on coals and sandstones is below 1%.Moreover,the minimum permeability recovery rate was above 66%.(2)For double-layer commingled reservoirs,the flow rate index revealed weak damage and the overall damage in double-layer was lower than the single-layer reservoirs.(3)There is no significant alteration in the microscopic structure of fuzzy-ball saturated cores with no evidence of fines *** dissolution of lead and sulfur occurred in coal samples,while tellurium in sandstone,aluminum,and magnesium in ***,the precipitation of aluminum,magnesium,and sodium occurred in sandstone but no precipitates found in coal and *** temporal plugging and dispersion characteristics of the FBWFs enable the generation of reservoir protection layers that will minimize formation damage due to solid and fluid invasion.

关键词： Drilling Fracture Fuzzy-ball fluids Formation damage analysis Muti-layer tight reservoirs Permeability damage index Flow rate damage index

Seasonal Dynamics of Turbidity Maximum in the Muthupet Estuary, India

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journal of Ocean University of China 2015年第5期14卷 765-777页

作者： PRIYA K.L. jEGATHAMBAL P. james E.j. School of Civil Engineering Karunya University

Results are presented of the longitudinal and vertical profiling of salinity and suspended particulate matter(SPM) at the Muthupet estuary, India, during a one year period under widely varying freshwater flow conditions. Freshwater flow was available during post-monsoon and monsoon. An up-estuary shift in the location of estuarine turbidity maxima(ETM) was observed during the transition from post-monsoon to pre-monsoon and further it shifted downstream during the transition from pre-monsoon to monsoon, thereby exhibiting a pronounced seasonal cycle. The salinity intrusion was dependent on the freshwater discharge and was expressed as a power function of freshwater flow, explaining 97% of the variance. The formation of a salt plug in Muthupet estuary and its seasonal dynamics were observed, which is not an identified feature of any of the Indian estuaries studied so far. The geographical positions of salt plug and ETM core were more or less the same during their formation. The occurrence of two ETM during the LW of post-monsoon and the absence of ETM during monsoon explains the strong seasonal variation in the formation of ETM. The primary factor affecting the formation of ETM was identified as the freshwater flow over an annual cycle; the resuspension of sediments by tidal current affecting the formation on a flood/ebb cycle was secondary. The extent of shift of ETM was found to be an inverse logarithmic function of the freshwater discharge. The separation between ETM intrusion and salinity intrusion increased two fold with the increase in ETM intrusion.

关键词： estuarine turbidity maximum salinity intrusion suspended particulate matter salt plug Muthupet estuary, India

Discussion of liquid threshold pressure gradient

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Petroleum 2017年第2期3卷 232-236页

作者： Xiukun Wang james j.Sheng Texas Tech University USA Southwest Petroleum University China

Some authors believe that a minimum pressure gradient(called threshold pressure gradient(TPG))is required before a liquid starts to flow in a porous *** a tight or shale oil formation,this TPG phenomenon becomes more important,as it is more difficult for a fluid to *** this paper,experimental data on TPG published in the literature are carefully *** we found is that a very low flow velocity corresponding to a very low pressure gradient cannot be measured in the *** can only be done above some measurable flow *** these flow velocities and their corresponding pressure gradients are plotted in an XY plot and extrapolated to zero velocity,a non-zero pressure gradient corresponds to this zero *** non-zero pressure gradient is called threshold pressure gradient in the ***,in the regime of very low velocity and very low pressure gradient,the data gradually approach to the origin of the plot,demonstrating a non-linear relationship between the pressure gradient and the *** the data do not approach to a point of zero velocity and a threshold pressure ***,the concept of threshold pressure gradient is a result of data misinterpretation of available experimental *** correct interpretation is that there are two flow regimes:nonlinear flow regime(non-Darcy flow regime)when the pressure gradients are low,and linear flow regime(Darcy flow regime)when the pressure gradient is intermediate or *** nonlinear flow regime starts from the origin *** the pressure gradient is increased,the curve becomes a straight line demonstrating the linear flow *** have verified our views by first analyzing the causes of non-Darcy flow,and then systematically analyzed typical experimental data and correlations in the *** conclude that TPG does not *** also use several counter examples to support our conclusion.

关键词： Low velocity non-Darcy flow Threshold pressure gradient Shale oil reservoirs Tight oil reservoirs

Leading Approaches to Vascularize Kidney Constructs in Tissue Engineering

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Engineering 2022年第12期19卷 117-127页

作者： Diana S.Lim john D.jackson Anthony Atala james j.Yoo Wake Forest Institute for Regenerative Medicine Wake Forest University School of MedicineMedical Center BoulevardNC 27157USA

There is an unprecedented need for new treatments for renal failure,as the incidence of this disease is increasing disproportionately to advancements in *** treatments are limited by the availability of viable organs,for which there is a worldwide *** treatment modalities also require a substantial amount of infrastructure,significantly limiting the access to care in most *** tissue engineering approaches promise to develop alternative solutions that address many of the inadequacies in current *** many advancements have been made—primarily in the past decade—in biofabrication and whole-organ tissue engineering,many challenges *** major hindrance to the progress of current tissue engineering approaches is establishing successful vascularization of developed engineered tissue *** review focuses on the recent advancements that address the vascular challenge,including the biofabrication of vasculature,whole-organ engineering through decellularization and recellularization approaches,microscale organogenesis,and vascularization using organoids in the context of kidney tissue *** also highlight the specific challenges that remain in developing successful strategies capable of clinical translation.

关键词： Kidney Vascularization Tissue engineering Biofabrication Organoids

Murine lung eosinophil activation and chemokine production in allergic airway inflammation

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Cellular & Molecular Immunology 2010年第5期7卷 361-374页

作者： C Edward Rose jr joanne A Lannigan Paul Kim james j Lee Shu Man Fu Sun-sang j Sung Division of Pulmonary and Critical Care Department of MedicineUniversity of Virginia School of MedicineCharlottesvilleVAUSA Department of Microbiology University of Virginia School of MedicineCharlottesvilleVAUSA Center for Immunity Inflammationand Regenerative Medicine and Division of NephrologyDepartment of MedicineUniversity of Virginia School of MedicineCharlottesvilleVAUSA Division of Pulmonary Medicine Department of Biochemistry and Molecular BiologyMayo Clinic ArizonaScottsdaleAZUSA

Eosinophils play important roles in asthma and lung *** models are widely used for assessing the functional significance and mechanistic basis for eosinophil involvements in these ***,little is known about tissue eosinophils in *** addition,little data on eosinophil chemokine production during allergic airway inflammation are *** this study,the properties and functions of homeostatic and activated eosinophils were *** from normal tissues expressed costimulation and adhesion molecules B7-1,B7-2 and ICAM-1 for Ag presentation but little major histocompatibility complex(MHC)class II,and were found to be poor stimulators of T-cell ***,these eosinophils expressed high levels of chemokine mRNA including C10,macrophage inflammatory protein(MIP)-1a,MIP-1c,MIP-2,eotaxin and monocyte chemoattractant protein-5(MCP-5),and produced chemokine *** intracellular chemokines decreased rapidly with concomitant surface marker downregulation upon in vitro culturing consistent with piecemeal *** eosinophils from mice with induced allergic airway inflammation exhibited increased chemokines mRNA expression and chemokines protein production and upregulated MHC class II and CD11c *** were also found to be the predominant producers of the CCR1 ligands CCL6/C10 and CCL9/MIP-1c in inflamed *** production of C10 and MIP-1c correlated with the marked influx of CD11bhigh lung dendritic cells during allergic airway inflammation and the high expression of CCR1 on these dendritic cells(DCs).The study provided baseline information on tissue eosinophils,documented the upregulation of activation markers and chemokine production in activated eosinophils,and indicated that eosinophils were a key chemokine-producing cell type in allergic lung inflammation.

关键词： allergy chemokines eosinophils lung mouse

Carbonaceous aerosol in ambient air: Parallel measurements between water cyclone and carbon analyzer

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Particuology 2019年第3期17卷 153-158页

作者： Min-Suk Bae james j. Schwab Da-jeong Park Zang-Ho Shon Ki-Hyun Kim Department of Environmental Engineering Mokpo National University Muan South Korea Atmospheric Sciences Research Center University at Albany State University of New York 251 Fuller Road Albany NY 12203 USA Environmental Analysis Center Gwangju Institute of Science and Technology Gwangju South Korea Department of Environmental Engineering Dong-Eui University Busan South Korea Department of Civil and Environmental Engineering Hanyang University Seoul South Korea

A water cyclone,developed to collect and preserve biological aerosols in a small liquid flow,was interfaced with a total organic carbon analyzer to measure the aerosol organic and inorganic carbon *** total carbon was compared against parallel measurements of elemental carbon (EC) and organic carbon (OC) using a Sunset Real Time ECOC Analyzer between 12-29 january 2009.A National Institute for Occupational Safety and Health (NIOSH) like protocol for the measurements included four temperature steps ending at 840 ℃ for OC under a helium atmosphere followed by two temperature steps ramped to 850 ℃ for EC in a helium-oxygen atmosphere,Carbon data comparison between the water cyclone-TOC and the TOC measured by the analyzer indicated good agreement (r2 =0.82,linear regression slope =0.98,p < 0.001).Analyses of the relationship between total water organic carbon and OC,investigated using data sets from case studies spanning two different events,suggested it was possible to distinguish between the primary and secondary sources.

关键词： Water soluble organic carbon Total organic carbon Carbonaceous material

Endophytic and pathogenic fungi of developing cranberry ovaries from flower to mature fruit:diversity and succession

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Fungal Diversity 2012年第3期54卷 101-116页

作者： Mariusz Tadych Marshall S.Bergen jennifer johnson-Cicalese james j.Polashock Nicholi Vorsa james F.White jr Department of Plant Biology and Pathology Rutgers University59 Dudley RoadNew BrunswickNJ 08901USA Philip E.Marucci Center for Blueberry and Cranberry Research and Extension Rutgers University125A Lake Oswego RoadChatsworthNJ 08019USA Genetic Improvement of Fruits and Vegetables Laboratory USDA-ARS125A Lake Oswego RoadChatsworthNJ 08019USA

Culturable fungal population diversity and succession was investigated in developing cranberry ovaries of fruit rot-resistant and rot-susceptible cranberry selections,from flower through mature *** were recovered in culture from 1185 of 1338 ovary tissues collected from june to September,yielding 2255 isolates that represented 42 *** the season,species richness varied from 2 to 17 and 2 to 18 in rot-resistant and rotsusceptible selections,respectively,increasing from wk1 to wk10 and then gradually declining to ***-Wiener diversity index varied from 0.27 to 2.32 in rotresistant and 0.18 to 2.38 in rot-susceptible,and Pielou’s evenness index varied from 0.11 to 0.63 and 0.06 to 0.64 in rot-resistant and rot-susceptible selections,respectively,confirming that diversity of fungi in developing ovaries was similar among rot-resistant and rot-susceptible selections,but varied among sampling time *** component analysis grouped samples collected at the same sampling time point together regardless of rot susceptibility of the selections,and detected the predominant fungal species associated with each stage of *** changes were observed in populations of endophytic,pathogenic and saprophytic fungi throughout the season as ovaries matured.

关键词： Aetiology Cranberry fruit rot Pathogens Phenology Resistance Vaccinium macrocarpon